Thankfully for those waiting until the last minute, the U.S. Postal Service is helping out this year.

Despite heavy budget constraints, the U.S. Postal Service is keeping its downtown office open until midnight Wednesday to service last-minute tax filers. Last year it closed early in an effort to cut costs.

TIPSHEET

Get marked: Returns must be postmarked by April 15 to avoid possible penalities.

Up late? Downtown Grand Rapids post office, 225 Michigan St. NW, is the only area office open until midnight Wednsday

Can't pay? File anyway. It's cheaper than the fine for not filing. The IRS has payment plans for those who owe taxes but can't afford to pay them.

Need more time? A six-month extension is allowed by filling out Form 4868 (it does not extend the due date for any taxes owed, however)

Questions? Talk to a tax professional, or visit IRS.gov, call 1-800-829-1040 or visit the Grand Rapids IRS service center's new location 3251 N. Evergreen Drive NE, north of 3 Mile Road off East Beltline Avenue.

Employees will be accepting stamped returns in front of the post office, 225 Michigan St. NW, and in front of The Grand Rapids Press headquarters, 155 Michigan St. NW.

Take heart if you've been putting off filing, average refunds are up 11 percent so far this tax season to $2,705, according to the IRS.

Those needing postage, proof of delivery or just the reassurance of seeing the postmark made on their tax returns can go inside the downtown branch for service.

U.S. Postal Service spokeswoman Gina Haisma said last-minute filers dropping returns in other mailboxes should take care to note the last pickup time for the box they are using to make sure they get the Wednesdaypostmark.

"For some people who may only need to mail something like this once a year for a postmark, that might not seem that obvious," she said.

Those who simply can't get their paperwork together by midnight Wednesday need only fill out IRS form 4868, which provides a free six month extension for completing forms. About 10 million taxpayers are expected to file for extensions this year.

Be warned, however, the extension does not give someone owing taxes an extension of time to pay. Late filers who owe money could face penalities for late payment.

Those who have their forms complete, should be sure to mail them even if they can't afford to pay the taxes they owe, according to the National Treasury Employees Union

The penalty for not filing is far greater than for not paying, the union notes.